Gas washing apparatus



Aug l1, 1959 E UMBRxcHT ETAL 2,899,183

GAS WASHING APPARATUS 2 Sheets-Sheet l Filed March 6, 1956 E MWC ,o N uTCA S mmL ,b w.. VBVI WN NMR. R IUG .MO S .l U oT LN A IA .m MR 1 EF .mW m Ali@ 11. 1959 E. UMBRlcHT Erm. v'2,899,183

Y GAS WASHING APPARATUS l Filed "March 6, 1956 2 Sheets-Sheet 2INVENToRs EMIL UMBRICHT ,2/ By FRANCIS GRYLANCE 2 -I y .mmn'm Q 50.\\on.

ATTORNEYS Eivonia, Mich;v

Application Maren' 6', '1956, se'rliarNd. 5658891" relaas.:(almere-221)."

invention relates to gas-washing apparatus is illustratively describedas embodied in air-washing apparatus of the type fused for removingparticles such as dustV or paint spray `from the" air.r Such air-washingapparatus is particularly well adapted for use` inconnection withindustriall spray painting,` polishing and sanding; operationsl andprevents the overspray material or dust-from th'ese processes fromcontaminating the surrounding-air and collecting upon nearby machinery.This apparatus greatly improves the extremely dicultl` workingconditions which formely used to` accompany these processes. The presentinvention isrinlthefnature of' a further improvement of gas-washing lapparatus now o n lein U.S. applications Serial Nos; 515,997 and458,336.

Among themany advantages ofthe airv'vashing apparatus described hereinasembodying this inventionI are those resulting from the fact-that-theapparatus a high efficiency and air-cleaning capacity. A relativelysmall installation handles a large; quantity of contaminated air,thoroughly: washing the airyrernovingsubstantially all foreign particlestherefrom, and 4returning the air to the `atmosphere in clean,relatively dry'condition.` It has become possible by the use of thisinvention kmarkedly to reduce the1 size of air-washing apparatus and yetto assure the user of-ecientandthorough treatment of a large quantity ofcontaminated air. Another advantage is the suitabilityof this apparatusfor` continuous operation in connection with massproduction industries.It requiresasubstantiallyy no'- maintenance or attention evenA duringoperation over long periods of time. Moreover, the compactnessofthe airwashing devicegdescribed herein, enables a manufacturer readilytoflocate the apparatus at an'y desired-point along an assemblylineBecause of the large size of previous air-washingap paratus, certainmanufacturing operations heretofore have required theuse of separatevrooms oi`th e employment of an--isolated corner of the factory to whichthe manufactured articles Were carried; In many cases this causedawkward arrangementsj'of the assembly. lines. -Now these operations canbe carried out 'smooth1y" inthe assembly lner- This inventionnotjonlyreduces the oor areabutflowers ftheminimum height- Yfrom thatrequired by other devices of similar capacity. A5 higher efficiency ofmanufacture results from yusing this device andl many heretoforeunusable spaces of a factory can now be utilzedto increase=the plantcapacity.

In -our co-pendingA applications `we have described a gas-washingapparatus having a single serpentine passage through which" thecontaminated gases pass and throughwhich, at a predetermined'rate, awashing liquid is directed against thepassage oftlie gas.` Theuhdlations of the serpentine passage desirably`-`create-a turbulenceatfcertain points in thepath of the gases whichh mixesfthe` Washingliquid' with the gas. Foreign particle's ventrained by `the1gas-arepicked up and conveniently carried oif by the Vwashing liquid.

States Patent 2,899,183 Patented Aug. 11, 1959 Inf the illustrativelembodiment of this invention We" use a :plurality of relatively small,pa rallel serpentine' passages arranged to deecti andsvvirl the airfrom'fside to side as; it passes through. These passages are Sider byside, the air in passing through the apparatus'issub divided uniformlyinto separate streams flowing upwardly through these passages. Thus,-each passage contributes? ecpuallygtol the airwashingjoperation: K

In the accompanying drawings;` weA have; shownfapreferred embodiment ofourinvention' and have -described the same inthe specification; it is"`to `be under-l stood that this description is not'intended to beexhaustive, but'on the contrary, is chosen forthe purpose o f -illu, s=trating. theinvention in order that others-skilled in- 'thel artmayfully understandthe invention,its'principles and, the applicationthereof and that Athey may; embody and; adapt it in various forms; each`as may be best suited to the requirements of its particular use,withoutvdepartingfrom the scope `of the claim.

Figure 1 shows a rear perspective View o f the air# washing apparatusvpartially broken away to disclose tlie multiple serpentine air passagescontainedjthereinf Figure 2 is a vertical sectionaliview'off the airWashing apparatus taken generally 'alongfthe line 2*-2 of Figure lvertical-ly through the center of the apparatus showing the path the airtakes upon entering and leavingAr onepfth'efseve'ral"serpentinepassages; Figure `3/ is a sectionalview on ahorizontal plane taken along-the line 3"-3 of Figure 2 lookingl down andillustrating the uniform vdistribution ofthe incoming-air as it passesinto the multiple serpentine` air passages.; A

Referring first to1Figures-l and 2, the Work piece, to be spray paintedor sanded or otherwise processedis conveyedinto and out of a boothpcloseto a front recess 2A of the air washingdevice. rIlle Work piecegis`maintained in this-position duri-ngthe spray painting or sandingoperationl The overspray pr dust'fr'orrr this operation is sucked by theair into the air-washingapparams-where it is eiiiciently'trappedandremoved from the air. The air= intake entrance 4 of thejgas-Washingapparatus is located at the lower end of a-flood sheetj 6 andY extendsacross thebottom of the air washer in the form of'a long rectangularopening. `Usually the amount ofoverspray ordust or other `foreignmaterial resulting from the industrial operation, being-carriedcn in/theregion 2 is far in" excessg of the quantity which can be suspended inthe air. For this reason thefoperatdr and location of thel work piece iss o arranged-that the foreign material is directed toward the ilopdsheet 6.A Ig ca tch this foreign material and carry itdown into `arese'rvoir tank 12 at the bottom from whieh itis conveniently removed`,a liquidi screen `8` continually ows down over this Hoodv sheet.VVAThis liquid sc reen advantageously: prevents -thefloodfsheet frombecoming-coatedmwith paintand dust. Liquid ispumped into a sp-ray pipe1Q, which'extends across the yfull width of the top' of' the rflood*sheet. Alongj the bottom lof this spray'pipe; are spaced a' number ofnozzles which direct a spray of liquid downwardlyandinwardly againsttheiiloodjs'heet, asseen in- 'Figure' 2. When the jdescenfding liquidscreen" 8 reaches the bottom edge 9; of the ood sheet `it cades, acrossthe" air intake'forming ajliquid curtain 11' and t hen falls-intothe-reservoir tank 1 2:

The` Washing liquid used is usually watercarrying in,` solution'suitable surfae-activeagents, detergents,anti

foamants', and rust-inhibitinglagents. And where paintL overspray isbeing-` handled, suitable paint killingA agents `are added, foreXamplef, such Vas thosehdisclo; in the co-p'ending US. applicationsofOrlan` M. varnold, senalfNa. 3'1'6,o'49 n -ledj'october' 21; 1952;- ana',issua as Patent No. 739;906; dated' M'fehfzv; 1956,"a 21jsria1'No-4'79go'3'2, l'd'neefbf '31,' v1954; ia'fhe names" of Arnold andHarbin. The foreign material is then removed from the liquid in thereservoir by suitable filtering and the liquid is recirculated throughthe apparatus. This filtering may advantageously be carried on byapparatus such as that disclosed by Emil Umbricht, Dewey Evans, andGerrit Steenhagen in copending application Serial No. 483,026, filedJanuary 20, 1955, now Patent No. 2,833,417, dated May 6, 1958. Thisrecirculation is carried on bywa suitable pump (not shown) having itsintake in the reservoir 12, for example, this pump may advantageously beas disclosed by Emil Umbricht in application Serial No. 357,450, filedMay 26, 1953, with its discharge connected to the pipe and Yalso to apipe 20, for reasons explained later.

The contaminated air in the front region 2 is drawn downwardV throughthe entrance 4 and is then sucked up into a number of serpentinepassages 18 by operation of a fan 13. The air in passing through theentrance 4 is given a further cleaning by passing through the liquidcurtain 11 descending from the flood sheet across the entrance 4.

Behind the entrance 4 is an intake chamber 15 defined by an upwardlycurved wall 16 and including an upwardly curved baliie 14 which smoothsthe air iiow as it is deflected upwardly into the serpentine passages.At the sameV time as the incoming air is being deflected upwardly, it isdivided by diverging baiiies 19 and 21 (please see also Figure 3). Theair thus separates uniformly and passes up into the serpentine passages18.

In Figure l, the rear of the air washing apparatus is shownvbroken awayto reveal the arrangement of these multiple serpentine passages. Thesepassages are defined by a number of box-like members 23, each having afiat bottom panel 34. Thesepanels close over the top of the intakechamber 15 except for the rectangular openings between them, seen mostclearly in Figure 3, which serve as the mouths of the serpentinepassages 18. The tops of these box-like members 23 are defined bytroughs 24 and downwardly sloping water sheds 26 and 28, whose purposeis explained later. Pairs of generally upright Asmoothly undulatingwalls 30 and 32 form the sides of the box-like members and define thesurfaces of the serpentine passages. These walls 30 and 32 may beuniformly spaced apart with the convex portions of one wall directlyopposite the concave portions of the adjacent wall or lthe walls may beincreased in distance apart from bottom to top. Thus, the crosssectional area of the serpentine passages 18 is constant throughout, or,in certain instances where these Walls 30 and 32 diverge somewhat in anupward direction, this cross sectional area increases gradually inprogressing from bottom to top of the individual passages 18.

The multiple serpentine passages 18 formed between these box-likemembers are generally parallel and identical. The contaminated air isdirected smoothly upward into them by the curved surfaces of the baffles14, 19 and 21. As soon as the air has entered a passageway 18 and beginsits upward ascent, it is swirled back and forth into intimate contactwith further washing liquid. This liquid is carried up from the pumpthrough a manifold pipe 20 and into individual supply pipes 22. Thesepipes 22 feed the liquid at a predetermined rate into each of thehorizontal supply troughs 24. The liquid overflows from the trough 24and main tains a continuously moving film of water on the inclined shedsurfaces 26 and 28. From these inclined surfaces 26 and 28 the water owsdown along the surfaces 30 and 32 of the serpentine passages 18. Theseinclined surfaces are connected to the tops of the two side walls of theadjacent serpentine passages as shown in Figure 1. Thus, with theexception of the two end troughs 35 and 36, each supply trough 24advantageously furnishes liquid to the two serpentine passages; eachtrough being located midway between one passage and the next so that owof water down both sides of each passage is assured.

This downward ow of water collects the particles of foreign matter whichare thrown against the walls 36 and 32 and thus further cleans the air.

The quantity of water which ows down each of the serpentine walls 30 and32 is slightly in excess of the water which can be retained on them bysurface tension. Theefore, under each convex portion 48 of these wallssome of the water falls away from the wall and drops across the airpassage and strikes the opposite wall. Similar release of the wateroccurs underneath other convex portions of the walls 30 and 32. Thus,because of the undulations along the air passage, water droplets cascadeback and forth across the air path and intimately mix with the air whichis in a swirling, turbulent condition at these points due to theundulations in the passages. The contaminating matter in the air isthereby thoroughly mixed with the descending water and is carried away.

After traveling through one of the several serpentine air passages andafter being cleaned by the cascading washing liquid in the respectivepassages the cleaned air then passes up into a plenum chamber 52. Thisplenum chamber is located in the gas-washing apparatus immediately abovethe multiple serpentine air washing passages and below a group ofmoisture eliminators 54. This plenum chamber is relatively large involume in relation to the total volume of the serpentine air passages,for the box-like members 23 which form the sides of the serpentinepassages occupy a large portion of the space in the lower part of theapparatus. Thus, advantageously, as the air emerges from the serpentinepassages and enters the plenum chamber 52 its velocity is sharplyreduced because the effective volume of the plenum chamber is muchgreater than the volume of the serpentine passages.

This sudden reduction in velocity drops out any remaining particlescarried by the air from the serpentine passages. s These particles dropdown and become trapped in the liquid films on the inclined sheds 26 and28. Then the air is drawn upward and passes through the moistureeliminators 54, constructed of a series of bent metal strips andarranged to provide a zig-zag path for the air. As the air passesthrough these moisture eliminators, any few remaining water droplets areremoved from the air as the droplets strike the metal strips in theeliminator. The clean air is then drawn on up and expelled to theatmosphere by the fan 13.

From the foregoing it will be understood that the embodiment of thepresent invention described above is well suited to provide the manyadvantages set forth, and since different embodiments may be made ofthis invention` and as the apparatus herein described may be varied invarious parts, all without departing from the scope of the invention, itis to be understood that all matter 'hereinbefore set forth or shown inthe accompanying drawings to be interpreted as illustrative and not in alimiting sense and that in certain instances, some of the features ofthe invention may be used without a corresponding use of other,features, or without departing from the scope of the invention.

We claim:

Apparatus for handling air having contaminating material entrainedtherein comprising a substantially vertical wall defining a flood sheethaving a substantially horizontal lower limit and means defining anelongated horizontal air entrance opening beneath the lower limit ofsaid ood sheet, first liquid supply means supplying liquid to the upperportion of said ood sheet and forming a liquid curtain owing down oversaid ood sheet and across said air entrance opening, a plurality ofcontinuously smoothly curved walls arranged in spaced generally uprightpositionsV and extending back behind said ood sheet, said walls havingvertically spaced concave and convex areas, pairs of adjacent Iwallsdefining a plurality of serpentine passages passing upwardlytherebetween, the lower limits of said serpentine passages beginningbehind said elongated horizontal air entrance opening at spaced pointstherealong, said serpentine passages Ihaving progressively increasingcross sectional areas from bottom to top, second liquid supply meansfeeding liquid at a controlled rate to the upper portions of all of saidserpentine passages, a plurality of vertically spaced horizontallyextending air deectors behind said air entrance opening and curvinginwardly and upwardly, the lower limits of said serpentine passagesbeginning above the inner upper limits of said air deectors, a pluralityof horizontally spaced vertically extending air dellectors, adjacentpairs of said latter deectors converging toward the respective lowerlimits of said serpentine passages, and blower means forcing thecontaminated air in through said vair entrance opening and upwardlythrough said serpentine passages.

References Cited in the file of this patent UNITED STATES PATENTS386,735 Armstrong July 24, 1888 2,077,427 Lissman Apr. 20, 1937y2,196,644 Rubel Apr. 9', 1940 2,198,305 Crawford Apr. 23, 19402,227,465 Roche et al. Jan. 7, 1941 2,231,088 Richardson Feb. 1l, 1941FOREIGN PATENTS 4,570 Great Britain July 8, 1909

